New Delhi  - India's main opposition Bharatiya Janata Party (BJP) is in a downward spiral, senior leader Jaswant Singh said Thursday, a day after the party expelled him.

Singh, who was minister of defence and finance in the former BJP-led government, was expelled from the BJP Wednesday after he praised Muhammad Ali Jinnah, the founder of neighboring Pakistan, in his recent book, Jinnah - India, Partition, Independence.

The Hindu right-wing BJP, which is holding a meeting of senior leaders in the northern Indian hill town of Shimla to discuss its defeat in the recent general election, had earlier disassociated itself from the contents of the book.

"The important role of MA Jinnah in the division of India, which led to a lot of dislocation and destabilization of millions of people, is too well-known. We cannot wish away this painful part of our history," an entry on the party's website said.

The BJP-led government of western Gujarat state banned the book which also criticizes India's first federal home minister Sardar Vallabhbhai Patel, a Gujarati, for his role in the partition of India.

"The day we start banning books, we are banning thinking," Singh was quoted as saying by PTI news agency.

Indian media reported that there was more to Singh's expulsion than his book on Jinnah.

"The decision is being read in the party as a stern message of zero tolerance to ideological deviation and indiscipline," veteran journalist Neena Vyas wrote in the Hindu newspaper.

The right-wing Hindu Rashtriya Swayamsevak Sangh, the BJP's ideological parent, has reportedly asked senior leaders of the party to put a lid on dissension.

Singh was among party insiders who criticized the BJP leadership for the defeat in the general elections and some recent appointments of office bearers.

A defeat in an election was a time to reflect, Singh earlier said in an interview with news channel NDTV.

"But the BJP has gone into an inward, downward spiral which is worrisome," he said.

Singh's book, which was published Monday, was selling briskly and was top of the non-fiction bestseller list in Delhi, IANS news agency reported. (dpa)